Creating a volume mesh before converting to 2D mesh?

westb · September 25, 2012, 23:03

Hi,

I'm running a basic simulation of a marble in steady flow and I want to use a 2D mesh to save computer memory. My question is: why do I have to volume mesh my geometry before converting it to a 2D mesh? Why do I have to wait a long time for the software to produce a 3D volume mesh, just to make it 2D afterwards?

Thanks

nomad · September 28, 2012, 16:02

Good question.

abdul099 · September 28, 2012, 17:13

Lol, why is it dark in the night?!? Does it help when I tell you, WHY you have to do it?
Even when you know the answer, you can't change it.

But when you want to solve on a 2D mesh, you don't need to mesh a huge 3D geometry. You can modify your geometry to be close to the 2D geometry you want to solve, e.g. cut a small slide out of your geometry.
That means, you still have to create a 3D mesh first, but you don't need to wait "a long time".

yonchong · September 28, 2012, 18:10

If you use the patch independent option 2-D mesh will be generated from surfaces rather than from the volume mesh.

westb · September 29, 2012, 14:17

Thanks for your responses. yonchong - is the patch independent option only an ANSYS option?

Thanks.

yonchong · September 29, 2012, 14:47

I am sorry I haven' t read your post properly.

For some reason I thought you are using ICEM for mesh generation.

If you generate surface mesh with ICEM You can choose whether you want to generate off the geometry surface (patch dependemt) or from 3d mesh (patch indepentant).

September 25, 2012, 23:03	Creating a volume mesh before converting to 2D mesh?	#1
westb New Member Join Date: Sep 2012 Posts: 3 Rep Power: 14	Hi, I'm running a basic simulation of a marble in steady flow and I want to use a 2D mesh to save computer memory. My question is: why do I have to volume mesh my geometry before converting it to a 2D mesh? Why do I have to wait a long time for the software to produce a 3D volume mesh, just to make it 2D afterwards? Thanks

September 28, 2012, 17:13		#3
abdul099 Senior Member Join Date: Oct 2009 Location: Germany Posts: 636 Rep Power: 22	Lol, why is it dark in the night?!? Does it help when I tell you, WHY you have to do it? Even when you know the answer, you can't change it. But when you want to solve on a 2D mesh, you don't need to mesh a huge 3D geometry. You can modify your geometry to be close to the 2D geometry you want to solve, e.g. cut a small slide out of your geometry. That means, you still have to create a 3D mesh first, but you don't need to wait "a long time". __________________ We do three types of jobs here: GOOD, FAST AND CHEAP You may choose any two!

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September 28, 2012, 16:02		#2
nomad Member John Join Date: Aug 2009 Posts: 92 Rep Power: 17	Good question.

September 28, 2012, 18:10		#4
yonchong Member Yon Han Chong Join Date: Jun 2012 Posts: 77 Rep Power: 14	If you use the patch independent option 2-D mesh will be generated from surfaces rather than from the volume mesh.

September 29, 2012, 14:17		#5
westb New Member Join Date: Sep 2012 Posts: 3 Rep Power: 14	Thanks for your responses. yonchong - is the patch independent option only an ANSYS option? Thanks.

September 29, 2012, 14:47		#6
yonchong Member Yon Han Chong Join Date: Jun 2012 Posts: 77 Rep Power: 14	I am sorry I haven' t read your post properly. For some reason I thought you are using ICEM for mesh generation. If you generate surface mesh with ICEM You can choose whether you want to generate off the geometry surface (patch dependemt) or from 3d mesh (patch indepentant).